Fucoidan, a fucose containing sulfated carbohydrate polymer, inhibits a wide range of physiological processes which involve cell interactions such as sperm-egg fertilization, tumor growth and the binding of lymphocytes to the endothelial cells of post-capillary venules. The preparation of polysulfated methyl fucosides of known structure will help elucidate the mechanism of these cell surface phenomena. Many polyanions bind to normal and sickle hemoglobin and affect its solubility. Highly sulfated trehalose has been shown to increase the solubility of hemoglobin-S. The synthesis of sulfated anions of appropriate size, which may have significant anti-sickling properties, is being pursued.